More questions from students today. We're going to cover gold as an investment, as promoted in advertisements; the value of neurofeedback as a medical treatment; Swedish snus compared to other smokeless tobacco; the rumor that the US government has millions of coffins ready so that they can execute us; and whether you should stop eating food and instead stare at the sun for all your nourishment. Let's get started with something that makes me stabby every time I see it on television:

Hi Brian, this is Gabe from Oklahoma. I've been hearing a lot about investing in Gold. Is this solid economics or just more crap? Thanks.

Buying gold is rarely a way to make a significant amount of money. The whole point of gold is its stability. When the market is up, stability is less important, and the value of gold drops somewhat; and when the market is down, investors seek to hold value and gold is one way to do that, so gold rises. But these shifts are relatively small compared to the market, and the smallness of those changes is what gold is all about. Over time, the value of gold generally keeps pace with inflation. Holding gold will never be a way to get rich.

However, anyone who's watched daytime television has seen advertisements hawking gold as the next big wave in investment, predicting massive increases in value. Just who is running these commercials; and if gold is such a great investment, why aren't they buying it themselves instead of buying TV ads to sell gold to you? That should tip you off. The companies running these advertisements are financial services companies. They are in the business of lending money, generally at high interest rates. They frankly don't care what you do with the loan, whether you buy gold with it or a jet ski; what they're after is the interest on your loan. Trust me, they make far more money off your interest than they would if they bought gold instead.

Some companies take it a step farther and stamp the gold into non-negotiable coins, often giving some impressive-sounding name for the coin to give the impression it's a valuable piece of currency, prized by collectors. Be skeptical. The vast majority of these are simply a way for them to sell you the gold at a price higher than its actual value as gold; but to anyone you might sell it to, it's only worth the gold it's made from, so you'll lose money. There are some exceptions. South African Krugerrands and American Eagle coins, for example, are minted by governments as a way to facilitate private ownership of gold and do have a value slightly higher than the bullion itself, but their price fluctuates in line with other gold; so they're really of no greater value than just a plain gold bar, just easier to buy and sell.

Hello, I'm Andrew from the Minneapolis College of Art and Design in Minnesota, and I would like to know if neurotherapy using EEG Biofeedback is an effective treatment?

Usually marketed as neurofeedback, this is an alternative therapy that claims to treat a huge range of conditions through the use of EEG biofeedback. You've probably seen TV shows where people, often with some paralysis or other handicap, practice moving a cursor on a computer screen using only electrodes attached to their scalp. You can indeed train your brain to do this kind of thing, and based on this apparent legitimacy, a whole cottage industry has grown around the sales and marketing of such machines, and expensive training for alternative practitioners to learn how to use them.

What's lacking is evidence of efficacy, or plausible foundation for how or why this might treat medical conditions. Practitioners can be found who claim it treats just about anything: autism, ADHD, incontinence, migraines, chronic pain, depression, drug abuse, sleep disorders, you name it. These disorders all have different underlying causes, so it's implausible to expect a single treatment to target more than one of them, let alone all of them.

The theory, as it's offered, is based on the premise that there are healthy brainwaves and unhealthy brainwaves. What you do is put on the electrodes and practice with whatever's on the screen, usually some type of simple video game, until the practitioner declares your EEG to look "healthier". The idea is that you come back again and again, practicing to reach the "healthy" EEG sooner; and it's claimed that this trains your brain to normally reach an improved state on its own. All of this sounds perfectly reasonable, and impressively high-tech, which is why the treatment is so easy to sell to uninformed patients.

Dramatic conditions like epileptic seizures and brain injuries can indeed have obvious readings on an EEG, but healthy brains also have a wide range of possible EEG waveforms. The notion that some healthy EEG waves are "good" and some are "bad" is without any neurological foundation, and thus, so is neurofeedback. "Bad" EEGs are neither characteristic of, nor the cause of, the conditions neurofeedback pretends to treat, so save your money.

Hi Brian, this is Brad Mitchell. I have heard a lot of hype lately about Swedish snus vs. other types of tobacco use. People are saying that there are less carcinogens and other harmful substances in snus. There was even a 60 Minutes piece on snus recently, with a doctor claiming it is 95-98% less harmful than smoking. There are also many articles and forums online suggesting this, claiming no medical or dental dangers, and a markedly lower occurrence in Sweden of cancer despite the high rate of tobacco use, mainly because it's almost exclusively snus. Is there any merit to this?

There is. Snus is a form of tobacco that you put in your mouth. Snuff, dip, chew, and snus are all slightly different, but they're all basically tobacco that you stick in your mouth (though some snuff is inhaled through the nose). Because there's no inhalation, they do not promote lung cancer, and that's where the huge reduction in overall cancer rates comes from. Sweden does indeed have a relatively low lung cancer rate, but this is not a benefit conferred by the use of snus, it's simply because almost nobody smokes there.

However, all nicotine products can contribute to pancreatic cancer and type 2 diabetes, and all oral tobacco products promote mouth and throat cancers. Because of the way snus is manufactured, it ends up with less nicotine and fewer carcinogens than other forms of oral tobacco. Most research does indeed confirm that snus is generally less harmful than other types of tobacco. But note that this only refers to Scandinavian snus; snus manufactured in the United States is made differently, and is generally just as carcinogenic as other smokeless tobacco products.

You're always better off avoiding all tobacco and nicotine products, even Scandinavian snus. Less harmful is still harmful.

Hi Brian. I was wondering if you examine the claim that FEMA has purchased thousands of alleged coffin liners for mass burial use.

If you Google the term "coffin liner" you'll see countless photographs of coffin-sized black plastic containers stored in huge numbers, apparently tens of thousands, in open fields, usually said to be in Georgia. You'll also find hundreds of forum threads on conspiracy theory websites like InfoWars.com and AboveTopSecret.com where paranoid people uncritically parrot the tired old claims that these are proof that FEMA, the Federal Emergency Management Agency, is planning to execute as many as several million Americans.

Because of all this chaff, I couldn't find any intelligent discussion of what these containers might actually be. If you know, come to the online transcript for this episode and tell us in the comment section.

But I can address the claim. FEMA has an unpleasant responsibility, and that's to handle large scale disasters like epidemics or attacks or natural disasters, in which large numbers of people might be killed. So it does make sense that they be prepared to handle lots of dead bodies. Whether these black plastic containers represent that readiness, I don't know, but it's consistent with what we'd expect. I couldn't find any reference to coffins with a cursory search of FEMA and other government websites.

Some of the forums marvel that FEMA would have coffins instead of just pushing bodies into mass graves with a bulldozer. The answer is simple: We have a little more respect for our dead than that, and also sometimes need to exhume for identification. If they think this is false, I invite them to cite examples of Americans being mass-buried by bulldozer inside the United States.

Why these would be called "coffin liners" by the conspiracy crowd, rather than simply coffins, escapes me. Coffin liners fit inside burial caskets, and can refer to moisture barriers or fancy padding. Neither is consistent with the large rectangular containers in the photographs.

Hello Brian. I'm Neil Laguardia from Ohlone College, and I've heard claims that sungazing has health benefits and that you have to 'do it properly'. What are your thoughts?

Sungazing is the practice of staring directly at the sun, thus allegedly gaining nourishment from it; and in some versions of the claim, replacing the need for food. These claims have never been studied, as it would clearly be unethical to have people deliberately damage their eyesight. Solar retinopathy, a burn to the retina from solar radiation, can cause temporary or permanent blindness.

As far as it replacing food, this is silly. Solar radiation does not contain any of the nutrients the human body needs, nor are there any anatomical structures capable of delivering nutrients through the eyes. Some claim that it works like photosynthesis. The closest thing to truth about this is that Vitamin D is synthesized in the skin by ultraviolet radiation striking a cholesterol precursor. Note that this happens in the skin, not the eyes; and you have to eat food to get the cholesterol to begin with; and Vitamin D is hardly the only thing our bodies need.

The few New Age gurus who claim to derive all their nutrition through sungazing have always been found to eat small amounts of food or drink, and there's no medical reason to suspect the sungazing is contributing to their nutrition. It's a foolish, dangerous, and implausible practice, so please don't try it.

Any other students out there have a question for Skeptoid? Come to Skeptoid.com, click on Student Questions, and follow the instructions. See if you can stump the Skeptoid.